You cannot go wrong with the factory Colt 11.5 or the Noveske offerings. I have an 11.5 Colt and a 10.5 Noveske. The 10.5 is my favorite. If I had to do it over I would get the lightest contour John offers. My only complaint is the weight of my upper. (Larue 7.0,krink brake, Troy flip ups, A/P CompM in larue mount and TD foregrip. Wes @MSTN or John@Noveske can build you a great upper. YMMV
Scott